Rugged Off Road 2 Inch rear block kit for 1999-2018 Chevy Silverado / GMC Sierra 1500Â 2wd and 4wd trucks. Provides either 2" of rear lift for trucks without a factory rear block, or 1" of lift if your truck has a factory rear block. Comes complete with vehicle specific u-bolts and hardware. Adds a nice rake for towing or hauling additional weight in the bed. Easy to install. Does not require any permanent modifications.